Strap for a tumbling device



Se t. 12, 1961 J, H. BOHRER, SR 2,999,553

STRAP FOR A TUMBLING DEVICE Filed July 51, 1957 flVVE/VZUE JOSEPH H.BOl-IRER, SP.

United States Patent Vania Filed July 31, 1957, Ser. No. 675,399 3Claims. (Cl. 182-139) This invention relates to gymnastic equipment and,more particularly, to trampolines.

Trampolines in the past have usually been made with a flexible surfaceattached to a frame by means of resilient devices which were, in somecases, in the form of metal springs and, in other cases, in the form ofelongated cords of resilient material. When metallic springs were used,there was a possibility that the person performing on the trampolinewould be injured by contact of this body with the resilient member. Inaddition, metal springs have resilient characteristics which are notalways desirable for use in a trampoline.

The present invention discloses a trampoline having improved resilientstraps. The straps are so designed as to keep the main portions of thestraps in a position remote from the performer and, therefore, avoidinadvertent contact with his body. The straps are so shaped that theygive a maximum resiliency for the size thereof.

ther advantages of the invention are:

(1) The end of the elastic member, providing means for engaging agrommet or other opening, is an integral part of the elastic member.

(2) No metal fitting is required such as hooks, clamps, and similarmetallic items otherwise used in previous devices.

(3) Positive protection against disengagement of the elastic memberunder normal use is provided as well as case of application, using onlyhousehold tools.

(4) Elimination of possible injury to the performer is provided bycompletely covering the metal grommet or other metal reinforcement whichit is engaging.

(5) An integral flanged member is incorporated into an elastic unit toprovide a means of attachment to other objects.

It is, accordingly, an object of the invention to provide a trampolinewhich is simple in construction, economical to manufacture, and simpleand efficient in operation.

Another object of the invention is to provide a trampoline having atumbling surface attached to a frame by means of tensioning memberswhich are made each of elastic material having an integral elasticheaded member which engages an opening in the tumbling surface whereinno metal fitting is required for attaching the tensioning members to thetumbling surface.

Still another object of the invention is to provide an improvedtensioning member made up of an elongated body of resilient materialhaving a headed member integrally attached thereto, the headed memberbeing attached to the tensioning member by means of a neck portion withan integral means on the other end of the tensioning member forattaching it to a frame.

A further object of this invention is to provide an improved tensioningmember for a tumbling device.

With the above and other objects in view, the present invention consistsof the combination and arrangement of parts hereinafter more fullydescribed, illustrated in the accompanying drawing and more particularlypointed out in the appended claims, it being understood that changes maybe made in the form, size, proportions, and minor details ofconstruction without departing from the spirit or sacrificing any of theadvantages of the invention.

In the drawing:

FIG. 1 is an isometric view of a tumbling device constructed inaccordance with a preferred embodiment of the invention;

FIG. 2 is an enlarged view of the improved tumbling surface with thetensioning member attached thereto; and

FIG. 3 is an enlarged view of the tensioning member which is animportant part of the invention.

Referring now to the drawing, a tumbling device or trampoline I. isshown having a tumbling surface or mat 10, preferably made of heavycanvas or the like, resiliently supported along its outer edges by aplurality of tensioning members 11. The members 11 are supported attheir outer ends from a more or less rectangular frame 12 of tubularsteel or the like having sides and ends defining an openingtherebetween. The frame 12 could be of any other particular designsuitable for supporting the tumbling surface 10 and is shown forpurposes of illustration only. The frame 12 is shown with U-shaped legs13 connected to the rectangular frame '12 at .14, 15 and '16. Lateralbraces 3-1 and 32 and end braces 41 are connected to the U-shaped legs13 by means of transverse members 36 attached to the lateral braces 31and 32 at their opposite ends and having the other end braces 41attached to the end of the rectangular frame 12 at an intermediatepoint.

The tumbling surface 10 may have a reinforcing strip 51 adjacent itsperipheral edge; however, the tumbling surface it} may comprise a singleheavy thickness of fabric or it may be made of two thicknesses of canvasas shown at 49 and 50 having the lateral reinforcing strip 51 extendingalong the underside of each edge and stitched to the tumbling surface 10as indicated at 52..

Grommets 39 are made of canvas pieces sewn to the upper surface of thetumbling surface 10 at 131. A head of the tensioning members 11 overliesa port of an upper surface 132 of the grommets 30 and an upper surface33 of the tensioning members 11. An elongated body 34 lies against thelower surface of the tumbling surface 10. Therefore, when the head 135is projected through the grommets 30, a neck 37 will lie in the hole inthe grommet 30 and the neck 37 itself will be of a diameter tocompletely fill the hole. The flanged edges of the head 135 will overliethe hole and the surface 33 will lie under and against the canvas,therefore holding the canvas firmly in shape.

The body 34 is preferably generally rectangular in cross section and hasan enlarged boss 49 on the end opposite the head 135. The boss 40 is ofconsiderably greater thickness than the body 34- and has a hole 411therethrough. The hole 411 receives a bolt 45 which may have its head 46covered with resilient material to prevent injury to a person tumblingon the tumbling surface 10. A lower end 141 of the bolt 45 extendsthrough an eye 48 in a hook 49. The hook 49 is made of fiat material andcurves around the frame member 12. The hook 49 can also be covered withresilient material to prevent injury to the person tumbling on thetumbling surface 10. The head :135, neck 37, body 34, and boss 40, allbeing made of an integral piece of resilient rubber like material, willnot injure the person tumbling on the surface 19 who may inadvertentlystrike the strap or any part thereof with his body.

The foregoing specification sets forth the invention in its preferredpractical forms but the structure shown is capable of modification within a range of equivalents without departing from the invention which isto be understood is broadly novel as is commensurate with the appendedclaims.

The embodiments of the invention in which an exclusive property orprivilege is claimed are defined as follows:

1. A tumbling device comprising a frame, a tumbling surface, tensioningmembers attaching said tumbling surface to said frame, said frame andend members defining an opening, each said tensioning member having oneend thereof attached to said tumbling surface and the other end thereofattached to said frame, said one end of each said tensioning memberhaving a head integrally attached thereto by means of a neck portion,spaced holes in said tumbling surface adjacent the periphery thereof,said neck portions each being disposed in one of said holes with saidheads having an outwardly directed flange overlying the top side of saidtumbling surface and the bodies of said tensioning members beingdisposed against the bottom side thereof below said tumbling surface,and means to attach the ends of said tensioning members opposite saidheads to said frame, said heads, neck portions, and bodies of saidtensioning members being made of resilient rubber like material.

2. The tumbling device recited in claim 1 wherein said means attachingsaid ends of said tensioning members to said frame comprises a boss oneach said tensioning member having an opening therethrough and hookmembers made of flat material, each said hook member having one enddisposed around said frame and the other end thereof attached to onesaid tensioning member by means of bolts each extending through one saidboss and through one said hook member.

comprising side members 2,999,558 r i w 3. The tumbling device recitedin claim 1 wherein said tensioning member body comprises a strap havingone dimension of its cross sectional area substantially greater than theother.

References Cited in the file of this patent UNITED STATES PATENTS404,862 Rabitte June 11, 1889 1,310,119 Harper June 15, 1919 1,892,841Kaufmann Jan. 3, 1933 1,987,921 Bertsch Ian. 15, 1935 2,190,764 ArnoldFeb. 20, 1940 2,370,990 Nissen Mar. 6, 1945 2,534,019 Griswold Dec. 12,1950 2,652,966 Griswold Sept. 22, 1953 2,809,383 Fenner Oct. 15, 1957FOREIGN PATENTS 41,747 Norway Aug. 17, 1925 388,671 Great Britain Mar.2, 1933 91,496 Sweden Feb. 17, 1938 1,080,695 France June 2, 1954

